PaleoJump database for research on rapid climate transitions

2021 ◽  
Author(s):  
Witold Bagniewski ◽  
Denis-Didier Rousseau ◽  
Michael Ghil
Keyword(s):  
Time Intervals ◽  
Origin Time ◽  
Essential Information ◽  
The Earth ◽  
Dating Methods ◽  
Long Time ◽  
Kolmogorov Smirnov ◽  
Paleoclimate Records ◽  
Smirnov Test ◽  
Climate Transitions

<p><span>Tipping poi</span><span>nts (TPs) in the </span><span>Earth system have been studied with growing interest and concern in recent years due to the potential risk of anthropogenic forcing causing abrupt, and possibly irreversible, climate transitions. Paleoclimate records are essential for identifying TPs in the Earth’s past and to properly understand the climate system’s underlying bifurcation mechanisms. </span><span>Due to their varying quality, resolution, and dating methods, it is often necessary to select the records that give the best representation of past climate. Furthermore, as paleoclimate records vary in their origin, time spans, and periodicities, an objective, automated methodology is crucial for identifying and comparing </span><span>TP</span><span>s. </span></p><p><span>To reach this goal, here we present the PaleoJump database of carefully selected, high-resolution records originating in ice, marine sediments, speleothems, loess, and lake sediments. These records, which include tipping elements, cover long time intervals and represent a global distribution from all continents and ocean basins. For every record, a transition detection methodology based on an augmented Kolmogorov-Smirnov test is applied to identify abrupt transitions. The PaleoJump database </span><span>highlights</span><span> these automatically detected transitions for every record together with other essential information, including location, temporal scale and resolution, as well as temporal plots; it therefore represents a valuable resource for researchers investigating TPs in past climates. This study is supported by</span> <span>the H2020-funded</span> <span>TiPES project.</span></p>

Review Lecture - Long time-scale fluctuations in the evolution of the Earth

1981 ◽  
Vol 375 (1760) ◽  
pp. 1-41 ◽  
Keyword(s):  
Current Knowledge ◽  
Interstellar Matter ◽  
The Sun ◽  
Time Intervals ◽  
Interstellar Clouds ◽  
The Earth ◽  
The Galaxy ◽  
Long Time ◽  
Extended Review ◽  
Review Current

This lecture is an attempt to review current knowledge about certain terrestrial phenomena with the twofold purpose: ( a ) to discover the extent to which the behaviour of the Earth may be influenced by fluctuations in its astronomical environment, ( b ) to see if new knowledge of that environment may be gained from its influence on the Earth. Fluctuations in geomagnetism, climate, glaciation, biological extinctions, etc., are surveyed with special regard to datings and characteristic time-intervals; correlations between such fluctuations are discussed. Astronomical phenomena, within the Solar System and elsewhere in the Galaxy, that might cause terrestrial effects are reviewed. As regards astronomical effects on Earth: (i) There is a good case - not yet overwhelming - for the currently widely accepted view that fluctuations of glaciation within an ice-epoch result from changes of insolation accompanying fluctuations of the Earth’s motion relative to the Sun. Some evidence suggests that an ice-epoch may be triggered by variations of the astronomical environment encountered in the Sun’s motion relative to the Galaxy; but tectonic changes on Earth may be the main trigger. (ii) Impacts of planetesimals may be more important than hitherto recognized. Among astronomical results regarding the Sun, while the intensity of solar ‘activity’ is variable, terrestrial effects provide no confirmation that the Sun is a ‘variable star’. Regarding the Galaxy, impacting planetesimals may originate in interstellar clouds, and so provide on Earth samples of interstellar matter. Some unsolved problems emphasized by the review are listed; certain concepts that would call for consideration in any extended review are mentioned.

scholarly journals Rers2014 and Mrs2014: New High-Precision Rigid Earth Rotation and Moon Rotation Series

2015 ◽  
Vol 50 (1) ◽  
pp. 35-40
Author(s):  
V.V. Pashkevich
Keyword(s):  
Numerical Solution ◽  
Numerical Investigation ◽  
High Precision ◽  
Rotational Motion ◽  
Earth Rotation ◽  
Euler Angles ◽  
Time Intervals ◽  
The Earth ◽  
Long Time ◽  
Rigid Earth

Abstract Numerical investigation of the Earth and Moon rotational motion dynamics is carried out at a long time intervals. In our previous studies (Pashkevich, 2013), (Pashkevich and Eroshkin, 2011) the high-precision Rigid Earth Rotation Series (designated RERS2013) and Moon Rotation Series (designated MRS2011) were constructed. RERS2013 are dynamically adequate to the JPL DE422/LE422 (Folkner, 2011) ephemeris over 2000 and 6000 years and include about 4113 periodical terms (without attempt to estimate new subdiurnal and diurnal periodical terms). MRS2011 are dynamically adequate to the JPL DE406/LE406 (Standish, 1998) ephemeris over 418, 2000 and 6000 years and include about 1520 periodical terms. In present research have been improved the Rigid Earth Rotation Series RERS2013 and Moon Rotation Series MRS2011, and as a result have been constructed the new high-precision Rigid Earth Rotation Series RERS2014 and Moon Rotation Series MRS2014 dynamically adequate to the JPL DE422/LE422 ephemeris over 2000 and 6000 years, respectively. The elaboration of RERS2013 is carried out by means recalculation of sub-diurnal and diurnal periodical terms. The residuals in Euler angles between the numerical solution and RERS2014 do not surpass 3 ìas over 2000 years. Improve the accuracy of the series MRS2011 is obtained by using the JPL DE422/LE422 ephemeris. The residuals in the perturbing terms of the physical librations between the numerical solution and MRS2014 do not surpass 8 arc seconds over 6000 years

From Kenorland to modern continents: tectonics and metallogeny

2019 ◽  
pp. 3-32
Author(s):  
A. S. Yakubchuk
Keyword(s):  
Continental Crust ◽  
Tectonic Evolution ◽  
Plate Tectonics ◽  
Ferrous Metal ◽  
Time Intervals ◽  
Secular Changes ◽  
The Earth ◽  
Time Space ◽  
Long Time ◽  
Three Stages

There are three stages in tectonic evolution of the Earth: (1) nucleation — from origin of protocratons to their assembly into Supercontinent Kenorland (2.7–2.5 Ga); (2) cratonization — from breakup of Kenorland (2.45 Ga) to the assembly of Columbia (1.85 Ga) and its reorganization into Rodinia (1.0–0.72 Ga); (3) modern plate tectonics — from breakup of Rodinia at 720 Ma until present. Analysis of time-space reorganizations of Archean granulite-gneiss terranes, which correspond to continental lithospheric keels, reveals five groups of protocratons (Nena, Ur, Congo-Sahara, NAsia and Atlantica) that remained almost intact during long time intervals. After the breakup of Kenorland, the continental crust rotated counter-clockwise. NAsia and Atlantica the least rotated and drifted relative to Nena, however the latter was rotated by 180°. Congo-Sahara, Ur and Kalahari were the most rotated. The assembly and breakup of the supercontinents clearly correlates with secular changes in dominant types of base, precious and ferrous metal deposits, as well as formation and emplacement of diamonds.

scholarly journals Optimal Perturbations of an Oceanic Vortex Lens

Fluids ◽  
2018 ◽  
Vol 3 (3) ◽  
pp. 63 ◽  
Author(s):  
Thomas Meunier ◽  
Claire Ménesguen ◽  
Xavier Carton ◽  
Sylvie Le Gentil ◽  
Richard Schopp
Keyword(s):  
Normal Mode ◽  
Growth Rates ◽  
Time Interval ◽  
Time Intervals ◽  
Horizontal Structure ◽  
Azimuthal Wave ◽  
Wave Numbers ◽  
Non Linear ◽  
Long Time ◽  
Short Time

The stability properties of a vortex lens are studied in the quasi geostrophic (QG) framework using the generalized stability theory. Optimal perturbations are obtained using a tangent linear QG model and its adjoint. Their fine-scale spatial structures are studied in details. Growth rates of optimal perturbations are shown to be extremely sensitive to the time interval of optimization: The most unstable perturbations are found for time intervals of about 3 days, while the growth rates continuously decrease towards the most unstable normal mode, which is reached after about 170 days. The horizontal structure of the optimal perturbations consists of an intense counter-shear spiralling. It is also extremely sensitive to time interval: for short time intervals, the optimal perturbations are made of a broad spectrum of high azimuthal wave numbers. As the time interval increases, only low azimuthal wave numbers are found. The vertical structures of optimal perturbations exhibit strong layering associated with high vertical wave numbers whatever the time interval. However, the latter parameter plays an important role in the width of the vertical spectrum of the perturbation: short time interval perturbations have a narrow vertical spectrum while long time interval perturbations show a broad range of vertical scales. Optimal perturbations were set as initial perturbations of the vortex lens in a fully non linear QG model. It appears that for short time intervals, the perturbations decay after an initial transient growth, while for longer time intervals, the optimal perturbation keeps on growing, quickly leading to a non-linear regime or exciting lower azimuthal modes, consistent with normal mode instability. Very long time intervals simply behave like the most unstable normal mode. The possible impact of optimal perturbations on layering is also discussed.

Age dependency of the diabetes effects on the iris recognition systems performance evaluation results

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Mohammadreza Azimi ◽  
Seyed Ahmad Rasoulinejad ◽  
Andrzej Pacut
Keyword(s):  
Iris Recognition ◽  
Recognition Task ◽  
Aging Effect ◽  
Recognition System ◽  
Health Condition ◽  
Age Dependency ◽  
Biometric Systems ◽  
Kolmogorov Smirnov ◽  
Recognition Systems ◽  
Smirnov Test

AbstractIn this paper, we attempt to answer the questions whether iris recognition task under the influence of diabetes would be more difficult and whether the effects of diabetes and individuals’ age are uncorrelated. We hypothesized that the health condition of volunteers plays an important role in the performance of the iris recognition system. To confirm the obtained results, we reported the distribution of usable area in each subgroup to have a more comprehensive analysis of diabetes effects. There is no conducted study to investigate for which age group (young or old) the diabetes effect is more acute on the biometric results. For this purpose, we created a new database containing 1,906 samples from 509 eyes. We applied the weighted adaptive Hough ellipsopolar transform technique and contrast-adjusted Hough transform for segmentation of iris texture, along with three different encoding algorithms. To test the hypothesis related to physiological aging effect, Welches’s t-test and Kolmogorov–Smirnov test have been used to study the age-dependency of diabetes mellitus influence on the reliability of our chosen iris recognition system. Our results give some general hints related to age effect on performance of biometric systems for people with diabetes.

Multifractal characterization of mechanical vibration signals through improved empirical mode decomposition-based detrended fluctuation analysis

2016 ◽  
Vol 231 (22) ◽  
pp. 4139-4149 ◽  
Author(s):  
Du Wenliao ◽  
Guo Zhiqiang ◽  
Gong Xiaoyun ◽  
Xie Guizhong ◽  
Wang Liangwen ◽  
...  
Keyword(s):  
Empirical Mode Decomposition ◽  
Detrended Fluctuation Analysis ◽  
Fluctuation Analysis ◽  
Intrinsic Mode Functions ◽  
Vibration Signals ◽  
Multifractal Detrended Fluctuation Analysis ◽  
Mode Decomposition ◽  
Kolmogorov Smirnov ◽  
Detrended Fluctuation ◽  
Smirnov Test

A novel multifractal detrended fluctuation analysis based on improved empirical mode decomposition for the non-linear and non-stationary vibration signal of machinery is proposed. As the intrinsic mode functions selection and Kolmogorov–Smirnov test are utilized in the detrending procedure, the present approach is quite available for contaminated data sets. The intrinsic mode functions selection is employed to deal with the undesired intrinsic mode functions named pseudocomponents, and the two-sample Kolmogorov–Smirnov test works on each intrinsic mode function and Gaussian noise to detect the noise-like intrinsic mode functions. The proposed method is adaptive to the signal and weakens the effect of noise, which makes this approach work well for vibration signals collected from poor working conditions. We assess the performance of the proposed procedure through the classic multiplicative cascading process. For the pure simulation signal, our results agree with the theoretical results, and for the contaminated time series, the proposed method outperforms the traditional multifractal detrended fluctuation analysis methods. In addition, we analyze the vibration signals of rolling bearing with different fault types, and the presence of multifractality is confirmed.

scholarly journals Relationship between oral habits and spirometry maneuvers, in children

Revista CEFAC ◽  
2018 ◽  
Vol 20 (1) ◽  
pp. 37-43
Author(s):  
Rafaela Coelho Minsky ◽  
Tayná Castilho ◽  
Roseane Rebelo Silva Meira ◽  
Tatiana Godoy Bobbio ◽  
Camila Isabel Santos Schivinski
Keyword(s):  
Healthy Children ◽  
Chi Square ◽  
Cross Sectional ◽  
Public And Private ◽  
Oral Habits ◽  
Qualitative Variables ◽  
Chi Square Test ◽  
Kolmogorov Smirnov ◽  
Thumb Sucking ◽  
Smirnov Test

ABSTRACT Purpose: to analyze whether deleterious oral habits can influence the number of attempts of forced spirometry maneuvers performed by healthy children. Methods: this observational and cross-sectional analytical study included 149 healthy children aged 6-12 years attending public and private schools in Florianópolis, SC, Brazil. A validated protocol was applied for the analysis of deleterious oral habits. The children were grouped according to the number of spirometry maneuvers needed to achieve successful spirometry results, as follows: G1) children who needed 3 maneuvers; G2) 4 maneuvers; G3) 5-8 maneuvers. Data were analyzed with the Kolmogorov-Smirnov test and the Kruskal-Wallis test was applied to compare quantitative variables between the groups. The Chi-square test was used to assess the association between the groups and qualitative variables. Results: there was no association between the number of attempts and the qualitative variables evaluated by the protocol. There was also no difference between the groups regarding quantitative variables for breastfeeding time, breastfeeding occurrence, use of pacifiers, and thumb sucking. Conclusion: the presence of DOH did not influence the number of forced spirometry maneuvers, performed by the healthy children in this study.

Investigation of The Nutritional Approaches of Student Athletes During The Covid-19 Epidemic

2021 ◽  
Vol 15 (7) ◽  
pp. 1940-1944
Author(s):  
Sevcan Altun ◽  
Aykut Aksu ◽  
Osman Imamoglu ◽  
Murat Erdogdu ◽  
Kursat Karacabey
Keyword(s):  
Student Athletes ◽  
Eating Habits ◽  
T Test ◽  
Outbreak Period ◽  
Significant Difference ◽  
Package Program ◽  
Kolmogorov Smirnov ◽  
The Subject ◽  
The University ◽  
Smirnov Test

The aim of this study is to investigate the nutritional approaches of student athletes studying at the university during the coronavirus outbreak period. Participants consisted of students studying and doing sports at the University. 446 students, 246 males and 200 females, participated in the study. Besides the personal form, students were filled the questionnaire testing questionnaire. Students voluntarily participated. The surveys were done on social media. Nutritional habits questionnaire consists of 12 questions. In the preparation of the survey questions, the questions proved validity of the researches which have been done on the subject before have been used. SPSS 23.00 package program was used in statistical analyses. Kolmogorov-Smirnov test was performed to test whether the data was normally distributed and it was determined that the data showed normal distribution. Independent t-test, paired t-test, unidirectional variance analysis and LSD tests were used in statistical operations. There was no significant difference in students' nutrition approaches by gender, both in the pre-outbreak period and in the outbreak period points (p> 0.05). Nutrition scores were significantly increased during the outbreak period (p <0.001). A significant difference was found between the students who felt bad before the epidemic and those who felt well before the epidemic and their nutritional scores according to the levels they felt (p <0.05). A significant difference was found between the pre-outbreak period and post-epidemic nutrition scores of the sports faculty students (p <0.05). During the coronavirus epidemic, university student athletes have either increased their nutritional opportunities or have changed their eating habits positively to keep their immune systems strong or both. The fact that sports faculty students have better nutrition compared to other faculty students can be attributed to their taking courses in nutrition, health and similar. It is recommended to give lectures or seminars on nutrition to athlete students. Keywords: Student, Nutrition, Sports Nutrition, Nutritional Approach, Covid-19

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